Expression and distribution of tenascin in rat submandibular glands following irradiation.

UNLABELLED The aim of this study was to investigate the late changes in the expression of tenascin-C (TN-C) in salivary glands (SG) following irradiation (IRR). MATERIALS AND METHODS In 124 submandibular SG from 62 Wistar rats, the effect of IRR dose (fractionated IRR, 2 Gy per day, total dose of 20, 40, or 60 Gy), time since IRR (6 months vs. 12 months), and animal age (1 year vs. 1.5 years) on TN-C expression profile and its distribution pattern was investigated. RESULTS Expression of TN-C showed slight to moderate alterations in the irradiated specimens. The expression differed in frequency and degree among various tissue structures. The most striking finding was pronounced dose-dependent heterogeneity, with increases, decreases and fluctuations in staining. CONCLUSION The staining of TN-C predominantly showed notable dose-dependent heterogeneity, persisting for up to 1 year after completion of IRR. Thus, these findings can be attributed to late radiation effects. The altered expression of tenascin-C may play at least a partial role in late radiogenic dysfunction of the submandibular SG.